1. Field of the Invention.
The present invention relates generally to the feeding of wild birds. More particularly, the invention relates to a substitute for Niger/Thistle seed wild bird food which includes a sunflower seed portion, a color coat, and a hydrophobic top coat produced from gluten meal and beef tallow. The invention also discloses a process to produce this product.
2. Description of the Prior Art.
The attraction of wild song birds to residential areas through feeding is a well-known practice. Tobin U.S. Pat. No. 4,246,869 discloses feeding Niger/Thistle seed or crushed sunflower seeds to small birds such as finches, siskins, red polls, and chicadees. The National Wildlife Federation, in Bulletin TZCD85, rates hulled sunflower 10 compared to a rating of 6 for Niger/Thistle seed, on a scale of 0-10, with 10 reflecting excellent acceptance by Goldfinches.
Most Niger/Thistle seed used for wild bird food in the United States is imported. This seed has a natural protective coating, but remains subject to insect infestation and contamination with foregin noxious weeds. Currently, the U.S.D.A. requires that all imported Niger/Thistle seed be heat treated to prevent germination of noxious weed seed. Unfortunately, such heat treatment of the Niger/Thistle seed tends to render it unpalatable to certain species of wild birds, especially finches.
Sunflower hearts, as currently supplied for wild bird feed, also have some well-known problems. These problems include insect infestation, moisture pickup, mold and chemical spoilage. Fazzolare U.S. Pat. No. 4,595,596 et al discloses coating sunflower seeds with zein and acetylated monoglycerides for use in baking. Alternative coatings include waxes, shellacs and resins. Other methods to improve stability of sunflower seeds in biscuits and crackers have included the use of antioxidants such as citric acid, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT). Fazzolare U.S. Pat. No. 4,761,296 discloses impregnating sunflower seeds with high stability vegetable oil to improve shelf life.
The prior art concerned with the exterior color of nuts, seeds and their substitutes includes several methods to change their appearance to the human eye. Some of these methods are concerned with attractive appearance to the human consumer. Sharma U.S. Pat. No. 4,522,833 discloses honey coated nuts. Durst U.S. Pat. No. 3,872,229 discloses artificial nuts coated with zein, wax, shellac or mono- and di-glycerides. Durst discloses the use of an edible color sprayed on an intermediate product of the artificial nuts to simulate a nut skin.
Other exterior color coating methods are concerned with facilitating identification of treated seeds to humans. Barke et al U.S. Pat. No. 4,368,591 discloses coating seeds with TiO.sub.2 and a yellow dye. The coatings help humans identify seeds that have been treated in various ways. For example, seeds treated with bird repellent could be readily identified by the altered colorings. Similarly, Porter et al U.S. Pat. No. 4,394,845 discloses a toluol based "blue plant paint" which aided in identifying coated seeds.
U.S. Pat. Nos. 3,032,422 and 2,792,509 disclose a nutritive food glaze based on zein.
U.S. Pat. No. 3,062,660 discloses treating raw nut meats with a zein coating.